Kimberly-Clark is suing Washington, DC, over a new city law that regulates when flushable wipes can be labeled “flushable.” According to a report by radio station WTOC in DC, the City Council unanimously passed legislation—The Nonwoven Disposable Products Act—on Dec. 6, 2016.

Councilmember Mary Cheh, D-Ward 3, who drafted the law, told the station: “We’re simply saying you have to say that they are not flushable unless you make them flushable.”

In the lawsuit that was filed in U.S. District Court, K-C attorneys say the law unfairly limits consumers’ right to choose products “that have been proven to effectively meet their needs without causing or contributing to clogs.”

The city, DC mayor Muriel Bowser, DC attorney general Karl Racine, DC Department of Energy and Environment director Tommy Wells and the District of Columbia Water and Sewer Authority are named as defendants.

K-C spokesman Bob Brand wrote in an email to the station: “We are not aware of any evidence that Kimberly-Clark flushable wipes caused a clog in the District or any other municipality for that matter. The evidence will show our flushable wipes meet or exceed widely accepted industry guidelines for flushability and the Federal Trade Commission’s standards on flushability,”

While the law has passed, it is not operational until the Department of Energy and Environment issues regulations about implementation, according to the report. Councilmember Cheh says it’s expected to go into effect in January 2018.